Last year, the show with the largest TV audience was Eastenders, which caused a 320MW demand spike as the end of the show coincided with a commercial break in Downton Abbey.

National Grid said the biggest Christmas Day pick-up to date followed an episode of Only Fools and Horses in 1996, with a pick-up of 1,340MW.

Energy forecasting manager Jeremy Caplin said: “TV pick-ups have reduced over recent years as many people now watch on demand, skip commercial breaks and there are hundreds of channels to choose from. The things that still give big pickups are sporting events, royal weddings and big TV events – anything people want to watch live and in real time.”

Each year, National Grid forecasters look at a range of past trends, behavioural data and detailed updates from the Met Office to work out how much electricity will be needed over the Christmas period.

The firm predicts a lunchtime peak of around of 35,410MW, compared with a busy teatime peak of 50,000MW.

The picture will be updated several times a day from now until 25 December, but predictions for mild and sunny weather have already caused the forecast to drop by around 2,000MW.

On Christmas Day, forecasters expect enough solar power on the system to cook 2.8 million turkeys – with around a quarter of those expected to be eaten.

Caplin said: “The pattern for Christmas Day is very different to the rest of the year. As factories, shops and offices close their doors, demand drops significantly and Christmas Day follows a different pattern to the one we see on a typical winter’s day.

“Demand rises steadily as people wake up and begin turning on their ovens to cook their turkeys and reaches a peak around lunchtime. Last year, Christmas Day had the lowest demand of the whole winter which was 36,357 MW – enough energy to light up 3.6 billion Christmas trees.”

Lois Vallely

This article first appeared in edie’s sister title, Utility Week

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